C#.net udp点对点聊天程序
客户端向服务器发起连接：
[csharp]
//设置服务IP，设置UDP端口号
ipep = new IPEndPoint(IPAddress.Parse(textBox1.Text), int.Parse(textBox2.Text)); //第一个参数是服务器ip地址，第二个参数是服务器端口号
//定义网络类型，数据连接类型和网络协议UDP
server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
Thread th = new Thread(new ThreadStart(myListen));<span style="white-space:pre"> </span>//建立一个线程，监听来自服务器的消息
th.IsBackground = true;<span style="white-space:pre"> </span>//IsBackground设置为true,则程序退出时，这个线程也会结束，否则就会一直开启
th.Start();
//设置服务IP，设置UDP端口号
ipep = new IPEndPoint(IPAddress.Parse(textBox1.Text), int.Parse(textBox2.Text)); //第一个参数是服务器ip地址，第二个参数是服务器端口号
//定义网络类型，数据连接类型和网络协议UDP
server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
Thread th = new Thread(new ThreadStart(myListen));<span style="white-space:pre"> </span>//建立一个线程，监听来自服务器的消息
th.IsBackground = true;<span style="white-space:pre"> </span>//IsBackground设置为true,则程序退出时，这个线程也会结束，否则就会一直开启
th.Start();
客户端监听来自服务器的消息:
[csharp]
private void myListen()
{
IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);
EndPoint Remote = (EndPoint)sender;
while (true)
{
if (ena)<span style="white-space:pre"> </span>//只有首先发送了，连接才能建立起来，所以ena在发送完第一条消息后设置为true
{
byte[] data = new byte[1024];
int recv = server.ReceiveFrom(data, ref Remote);
richTextBox1.AppendText(Encoding.Default.GetString(data));
}
}
}
private void myListen()
{
IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);
EndPoint Remote = (EndPoint)sender;
while (true)
{
if (ena)<span style="white-space:pre"> </span>//只有首先发送了，连接才能建立起来，所以ena在发送完第一条消息后设置为true
{
byte[] data = new byte[1024];
int recv = server.ReceiveFrom(data, ref Remote);
richTextBox1.AppendText(Encoding.Default.GetString(data));
}
}
}
客户端向服务器发送消息：
[csharp]
byte[] b = Encoding.Default.GetBytes(textBox3.Text + ":/n" + textBox7.Text+"/n");
server.SendTo(b, b.Length, SocketFlags.None, ipep);
richTextBox1.AppendText(textBox3.Text + ":/n" + textBox7.Text + "/n");
ena = true;
byte[] b = Encoding.Default.GetBytes(textBox3.Text + ":/n" + textBox7.Text+"/n");
server.SendTo(b, b.Length, SocketFlags.None, ipep);
richTextBox1.AppendText(textBox3.Text + ":/n" + textBox7.Text + "/n");
ena = true;
服务器开始监听：
[csharp]
//得到本机IP，设置UDP端口号
ipep2 = new IPEndPoint(IPAddress.Any, int.Parse(textBox9.Text));
newsock2 = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
//绑定网络地址
newsock2.Bind(ipep2);
Thread thread = new Thread(new ThreadStart(serverListen));<span style="white-space:pre"> </span>//监听来自客户端发来的消息
thread.IsBackground = true;
thread.Start();
//得到本机IP，设置UDP端口号
ipep2 = new IPEndPoint(IPAddress.Any, int.Parse(textBox9.Text));
newsock2 = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
//绑定网络地址
newsock2.Bind(ipep2);
Thread thread = new Thread(new ThreadStart(serverListen));<span style="white-space:pre"> </span>//监听来自客户端发来的消息
thread.IsBackground = true;
thread.Start();
服务器监听来自客户端发来的消息：
[csharp]
//得到客户机IP
IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);
Remote = (EndPoint)(sender);
while (true)
{
byte[] data = new byte[1024];
newsock2.ReceiveFrom(data, ref Remote);
button4.Enabled = true;
// textBox4.Text = sender.Address.ToString(); //目前无法通过这样获得客户端ip和端口号
// textBox5.Text = sender.Port + "";
richTextBox2.AppendText(Encoding.Default.GetString(data));
}
//得到客户机IP
IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);
Remote = (EndPoint)(sender);
while (true)
{
byte[] data = new byte[1024];
newsock2.ReceiveFrom(data, ref Remote);
button4.Enabled = true;
// textBox4.Text = sender.Address.ToString(); //目前无法通过这样获得客户端ip和端口号
// textBox5.Text = sender.Port + "";
richTextBox2.AppendText(Encoding.Default.GetString(data));
}服务器想客户端发送消息:
[csharp]
byte[] b = Encoding.Default.GetBytes(textBox6.Text + ":/n" + textBox8.Text+ "/n");
//发送信息
newsock2.SendTo(b, b.Length, SocketFlags.None, Remote);
richTextBox2.AppendText(textBox6.Text + ":/n" + textBox8.Text + "/n");
byte[] b = Encoding.Default.GetBytes(textBox6.Text + ":/n" + textBox8.Text+ "/n");
//发送信息
newsock2.SendTo(b, b.Length, SocketFlags.None, Remote);
richTextBox2.AppendText(textBox6.Text + ":/n" + textBox8.Text + "/n");
截图如下：
